Defluoridation from aqueous solutions by granular ferric hydroxide (GFH)
Eva Kumar1, Amit Bhatnagar, Minkyu Ji
1Department of Environmental Engineering, Baekun Hall #332, Yonsei University, 234 Maeji Heungeop, Wonju, 220-710 Gangwon-do, South Korea.
Water Research
|November 11, 2008
Summary
Granular ferric hydroxide (GFH) effectively removes fluoride from water. This study shows GFH is a promising material for developing efficient fluoride removal technologies for drinking water.
Area of Science:
- Environmental Science
- Water Treatment Technology
- Adsorption Science
Background:
- Fluoride contamination in water poses health risks.
- Effective removal methods are crucial for safe drinking water.
- Granular ferric hydroxide (GFH) is a potential adsorbent material.
Purpose of the Study:
- To evaluate the feasibility of granular ferric hydroxide (GFH) for fluoride removal.
- To investigate the adsorption kinetics and capacity of GFH for fluoride.
- To determine the influence of various parameters on fluoride adsorption by GFH.
Main Methods:
- Batch adsorption experiments were conducted.
- Influences of contact time, initial fluoride concentration, temperature, pH, and competing anions were studied.
- Kinetic and isotherm models (pseudo-first-order, pore diffusion, Langmuir) were applied.
Main Results:
- GFH demonstrated rapid fluoride uptake, with 95% removal in 10 minutes and equilibrium in 60 minutes.
- The maximum adsorption capacity was 7.0 mg/g.
- Optimal fluoride removal occurred between pH 4-8, and adsorption was endothermic.
- Phosphate, carbonate, and sulfate ions reduced fluoride adsorption.
Conclusions:
- Granular ferric hydroxide (GFH) is a highly effective adsorbent for fluoride removal from aqueous solutions.
- The adsorption process follows pseudo-first-order kinetics and Langmuir isotherm.
- GFH shows significant potential for developing practical fluoride removal technologies for drinking water.
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